Free Writing Programs

OpenOffice
- (Windows, Mac OS X, Linux); Specifically what you are looking for here is Writer. It's a full featured word processor.

FreeMind
- (Windows, Mac OS X, Linux); Mind mapping software

KeyNote
- (Windows); Organizes your notes

yWriter
- (Windows); A word processing program with a few extras.

Stickies
- (Windows); Virtual Post It notes

Collanos Workplace
(Windows, Mac OS X, Linux); Synchronizes information between multiple computers or users.

Sonar
- (Windows); Tracks submissions

Space Jock